49 research outputs found

    The performance of socially responsible mutual funds: the role of fees and management companies

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    In this paper, we shed light on the debate about the financial performance of socially responsible investment (SRI) mutual funds by separately analyzing the contributions of before-fee performance and fees to SRI funds' performance and by investigating the role played by fund management companies in the determination of those variables. We apply the matching estimator methodology to obtain our results and find that in the period 1997-2005, US SRI funds had significantly higher fees and better before- and after-fee performance than conventional funds with similar characteristics. Differences, however, were driven exclusively by SRI funds run by management companies specialized in socially responsible investment

    Mar Menor lagoon (SE Spain) chlorophyll-a and turbidity estimation with Sentinel-2

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    Mar Menor is a Mediterranean Coastal lagoon with high environmental and social value, but has suffered important episodes of contamination in recent years due to heavy rains, sediment dragging and polluting substances mainly from agriculture as well as the entry of mining waste, causing an increase in eutrophication. Water quality variables such as chlorophyll-a concentration [Chl-a] and turbidity, can be studied through its optical properties by remote sensing techniques. In this work, a methodology is proposed for monitoring [Chl-a] and the turbidity of the Mar Menor using Sentinel-2 images. For this purpose, an extensive database of both variables was used consisting of data taken on different dates between 2016 and 2019 at 12 points of Mar Menor. The images were atmospherically corrected using Case 2 Regional Coast Color Processor (C2RCC) version for turbid waters (C2X) to obtain the water surface reflectance. Then several arithmetic relations between database and reflectance bands used in the bibliography for [Chl-a] and turbidity were analyzed. Comparing the results of each one of these relations with the in situ data, decided that the best index for [Chl-a] estimation is the relation (R560 + R705)/ (R560 + R665) with an RMSE = 2.6 mg/m3 and a NRMSE = 9.1 % and for turbidity R705*R705/R490 with an RMSE = 1.5 NTU and a NRMSE= 10.9 %. Finally, by applying these relationships on different dates, thematic maps of [Chl-a] and turbidity of Mar Menor were obtained. One of these images was some days after September 2019 torrential rains, in which a considerable [Chl-a] and turbidity increase was observed

    Turbidity and Secchi disc depth with Sentinel-2 in different trophic status reservoirs at the Comunidad Valenciana

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    [ES] En los estudios de calidad de aguas por teledetección, uno de los principales indicadores es la transparencia o turbidez del agua. La transparencia puede ser medida in situ mediante la profundidad del disco de Secchi (SD), y la turbidez con un turbidímetro. En las últimas décadas se han utilizado diferentes relaciones entre bandas de diferentes sensores obtenidas por teledetección para la estimación de estos parámetros. En este trabajo, a partir de datos de campo obtenidos a lo largo de 2017 y 2018 en embalses de la cuenca del Júcar con gran variedad de estados tróficos, se han calibrado diferentes índices y bandas para poder estimar la transparencia a partir de imágenes Sentinel-2 (S2). A las imágenes S2 nivel L1C tomadas en el mismo día que los datos de campo, se les han aplicado tres métodos de corrección atmosférica desarrollados para aguas: Polymer, C2RCC y C2X. A partir de los espectros de S2 obtenidos y de los datos de campo de SD se ha observado que el menor error se obtiene con las imágenes corregidas con Polymer y un ajuste potencial del cociente de reflectividades en las bandas azul y verde (R490/R560), que permiten la estimación de SD con un error relativo del 13%. También el método C2X presenta buen ajuste con el mismo cociente de bandas, aunque un error mayor, presentando la corrección C2RCC la peor correlación. Se ha obtenido también la relación entre SD (en m) y turbidez (en NTU), lo que proporciona un método operativo para la estimación de la turbidez con S2. Se muestra, además, la relación para los diferentes embalses entre el SD y la concentración de clorofila-a, sólidos en suspensión y materia orgánica disuelta.[EN] Transparency or turbidity is one of the main indicators in studies of water quality using remote sensing. Transparency can be measured in situ through the Secchi disc depth (SD), and turbidity using a turbidimeter. In recent decades, different relationships between bands from different remote sensing sensors have been used for the estimation of these variables. In this paper, several indices and spectral bands have been calibrated in order to estimate transparency from Sentinel-2 (S2) images from field data, obtained throughout 2017 and 2018 in Júcar basin reservoirs with a great variety of trophic states. Three atmospheric correction methods developed for waters have been applied to the S2 level L1C images taken at the same day as the field data: Polymer, C2RCC and C2X. From the spectra obtained from S2 and the SD field data, it has been found that the smallest error is obtained with the images atmospherically corrected with Polymer and a potential adjustment of the reflectivities’ ratio of the blue and green bands (R490/R560), which allow the estimation of SD with a relative error of 13%. Also the C2X method presents good adjustment with the same bands ratio, although with a greater error, while the correction C2RCC shows the worst correlation. The relationship between SD (in m) and turbidity (in NTU) has also been obtained, which provides an operational method for estimating turbidity with S2. The relationship for the different reservoirs between SD and chlorophyll-a concentration, suspended solids and dissolved organic matter, is also shownEste trabajo ha sido posible gracias al Proyecto ESAQS del Programa Prometeo para grupos de investigación de excelencia de la Conselleria d’Educació, Investigació, Cultura i Esport (GVPROMETEO2016-132) de la Generalitat Valenciana.Delegido, J.; Urrego, P.; Vicente, E.; Sòria-Perpinyà, X.; Soria, J.; Pereira-Sandoval, M.; Ruiz-Verdú, A.... (2019). Turbidez y profundidad de disco de Secchi con Sentinel-2 en embalses con diferente estado trófico en la Comunidad Valenciana. Revista de Teledetección. 0(54):15-24. https://doi.org/10.4995/raet.2019.12603OJS1524054Alikas, K., Kratzer, S. 2017. Improved retrieval of Secchi depth for optically-complex waters using remote sensing data. Ecological indicators, 77, 218- 227. https://doi.org/10.1016/j.ecolind.2017.02.007Ansper, A., Alikas, K. 2019. Retrieval of Chlorophyll-a from Sentinel-2 MSI Data for the European Union Water Framework Directive Reporting Purposes. Remote Sensing, 11, 64. https://doi.org/10.3390/rs11010064APHA, 1992. Standard methods for the examination of water and wastewater. 18th edition. American Public Health Association. Washington D.C., USA. 1105 pp.Baughman, C.A., Jones, B.M., Bartz, K.K., Young, D.B., Zimmerman, C.E. 2015. Reconstructing Turbidity in a Glacially Influenced Lake Using the Landsat TM and ETM+ Surface Reflectance Climate Data Record Archive, Lake Clark, Alaska. Remote Sensing, 7, 13692-13710. https://doi.org/10.3390/rs71013692Brockmann, C., Doerffer, R., Peters, M., Kerstin, S., Embacher, S., Ruescas, A. 2016. Evolution of the C2RCC neural network for Sentinel 2 and 3 for the retrieval of ocean colour products in normal and extreme optically complex waters. In Proceedings of the "ESA Living Planet Symposium 2016", Prague, Czech Republic, 9-13 May 2016.Delegido, J., Urrego, P., Ruiz-Verdú, A., PereiraSandoval, M., Vicente, E., Sòria-Perpinyà, X., Soria, J.M., Moreno, J. 2019. Transparencia de diferentes embalses de la cuenca del Júcar con imágenes Sentinel-2. XVIII Congreso de la Asociación Española de Teledetección. Valladolid, 24-27 septiembre 2019.Doron, M., Babin, M., Mangin, A., Hembise, O. 2007. Estimation of light penetration, and horizontal and vertical visibility in oceanic and coastal waters from surface reflectance. J. Geophys. Res., 112, C06003. https://doi.org/10.1029/2006JC004007Gholizadeh, M.H., Melesse, A.M., Reddi, L. 2016. A Comprehensive Review on Water Quality Parameters Estimation Using Remote Sensing Techniques. Sensors, 16(8), E1298. https://doi.org/10.3390/s16081298Jeffrey, S.T., Humphrey, G.F. 1975. New spectrophotometric equations for determining chlorophylls a, b, c1 and c2 in higher plants, algae and natural phytoplankton. Biochem. Physiol. Pflanz., 167, 191-194. https://doi.org/10.1016/S0015-3796(17)30778-3Khorram, S., Cheshire, H., Geraci, A.L., Rosa, G.L., 1991. Water quality mapping of Augusta Bay, Italy from Landsat-TM data. Int. J. Remote Sens., 12(4), 803- 808. https://doi.org/10.1080/01431169108929696Koponen, S., Pulliainen, J., Kallio, K., Hallikainen, M. 2002, Lake water quality classification with airborne hyperspectral spectrometer and simulated MERIS data. Remote Sensing of Environment, 79, 51-59. https://doi.org/10.1016/S0034-4257(01)00238-3Korshin, G.V., Li, C.W., Benjamin, M.M. 1997. Monitoring the properties of natural organic matter through UV spectroscopy: A consistent theory. Water Research, 31, 1787-1795. https://doi.org/10.1016/S0043-1354(97)00006-7Kratzer, S., Brockmann, C., Moore, G. 2008. Using MERIS full resolution data to monitor coastal waters - A case study from Himmerfjärden, a fjordlike bay in the northwestern Baltic Sea. Remote Sensing of Environment, 112(5), 2284-2300. https://doi.org/10.1016/j.rse.2007.10.006Lee, Z., Shang, S., Hu, C., Du, K., Weidemann, A., Hou, W., Lin, J., Lin, G. 2016. Secchi disk depth: a new theory and mechanistic model for underwater visibility. Remote Sens. Environ., 169, 139-149. https://doi.org/10.1016/j.rse.2015.08.002Matthews, M.W. 2011. A current review of empirical procedures of remote sensing in inland and near-coastal transitional waters. International Journal of Remote Sensing, 32(21), 6855-6899. https://doi.org/10.1080/01431161.2010.512947Mosquera, A., Torres, J.M., González-Vilas, L., Martínez-Iglesias, G., Pazos, Y. 2006. Estudio de una floración tóxica de Pseudonitzschias sp. en las costas de Galicia usando una imagen MERIS y datos in situ. Revista de Teledetección, 25, 75-79. Disponible en: http://www.aet.org.es/revistas/revista25/AET25- 15.pdf. Último acceso: Diciembre de 2019.Mueller, J. L. 2000. SeaWiFS algorithm for the diffuse attenuation coefficient, K (490), using water-leaving radiances at 490 and 555 nm. SeaWiFS Postlaunch Calibration and Validation Analyses, part 3, edited by S. B. Hooker, pp. 24-27, NASA Goddard Space Flight Center.Page, B., Kumar, A., Mishra, D. 2018. A novel crosssatellite based assessment of the spatio-temporal development of a cyanobacterial harmful algal bloom. Int. J. Appl. Earth Obs. Geoinf., 66, 68-81. https://doi.org/10.1016/j.jag.2017.11.003Page, B., Olmanson, L., Mishra, D. 2019. A harmonized image processing workflow using Sentinel-2/MSI and Landsat-8/OLI for mapping water clarity in optically variable lake systems. Remote Sens. Environ., 231, 111284. https://doi.org/10.1016/j.rse.2019.111284Pahlevan, N., Chittimalli, S., Balasubramanian, S., Vellucci, V. 2019. Sentinel2/Landsat8 product consistency and implications for monitoring aquatic systems. Remote Sens. Environ., 220, 19-29. https://doi.org/10.1016/j.rse.2018.10.027Pereira-Sandoval, M., Ruescas, A.B., Urrego, P., Delegido, J., Ruiz-Verdú, A, Tenjo, C., SoriaPerpinyà, X., Vicente, E, Soria, J., Peña, R., Moreno, J. 2018. Evaluación de métodos de corrección atmosférica sobre imágenes Sentinel2-MSI en aguas continentales. XVIII Simposio Internacional SELPER y Sistemas de Información Espacial, Noviembre de 2018, La Habana, Cuba.Pereira-Sandoval, M., Urrego, P., Ruiz-Verdú, A., Tenjo, C., Delegido, J., Soria-Perpinyà, X., Vicente, E., Soria, J., Moreno, J. 2019a. Calibration and validation of algorithms for the estimation of chlorophyll-a concentration and Secchi depth in inland waters with Sentinel-2. Limnetica, 38(1), 471- 487. https://doi.org/10.1109/IGARSS.2018.8517371Pereira-Sandoval, M., Ruescas, A., Urrego, P., RuizVerdú, A., Delegido, J., Tenjo, C, Soria-Perpinyà, X., Vicente, E., Soria, J., Moreno, J. 2019b. Evaluation of Atmospheric Correction Algorithms over Spanish Inland Waters for Sentinel-2 Multi Spectral Imagery Data. Remote Sensing, 11, 1469. https://doi.org/10.3390/rs11121469Shoaf, W.T., Lium, B.W. 1976. Improved extraction of chlorophyll a and b from algae using dimethyl sulphoxide. Limnol. Oceanogr., 21, 926-928. https://doi.org/10.4319/lo.1976.21.6.0926Soria, X., Vicente, E., Durán, C., Soria, J.M., Peña, R. 2017. Uso de imágenes Landsat-8 para la estimación de la profundidad del disco de Secchi en aguas continentales. XVII Congreso de la Asociación Española de Teledetección. pp. 293-296. Murcia 3-7 octubre 2017.Sòria-Perpinyà, X., Urrego, P., Pereira-Sandoval, M., Ruiz-Verdú, A., Peña, R., Soria, J.M., Delegido, J., Vicente, E., Moreno, J. 2019. Monitoring the ecological state of a hypertrophic lake (Albufera of València, Spain) using multitemporal Sentinel-2 images. Limnetica, 38(1), 457-469. https://doi.org/10.23818/limn.38.26Steinmetz, F., Deschamps, P.Y., Ramon, D. 2011. Atmospheric correction in presence of sun glint: Application to MERIS. Optics Express, 19(10), 9783-800. https://doi.org/10.1364/OE.19.009783Toming, K., Kutser, T., Laas, A., Sepp, M., Paavel, B., Nõges, T. 2016. First experiences in mapping lake water quality parameters with Sentinel-2 MSI imagery. Remote Sens., 8, 640. https://doi.org/10.3390/rs8080640Tyler, A.N., Hunter, P.D., Spyrakos, E., Groom, S., Constantinescu, A.M., Kitchen, J. 2016. Developments in Earth observation for the assessment and monitoring of inland, transitional, coastal and shelf-sea waters. Sci. Total Environ., 572, 1307-1321. https://doi.org/10.1016/j.scitotenv.2016.01.020Zhao, D., Cai, Y., Jiang, H., Xu, D., Zhang, W., An, S. 2011. Estimation of water clarity in Taihu Lake and surrounding rivers using Landsat imagery. Advances in Water Resources, 34(2), 165-173. https://doi.org/10.1016/j.advwatres.2010.08.01

    Nuevos datos sobre la distribución de mamíferos (Mammalia) en las dunas de Erg Chebbi (Marruecos)

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    The progressive increase of adventure tourism in the area around the dunes of Erg Chebbi has threatened, for almost two decades, the conservation of the only dune complex (Erg) of Morocco. In order to assess some of the effects of this activity on the local mammal communities, an intensive sampling was carried out between March and April 2018, based on 5 different detection methods. The main objective was to evaluate the presence and current distribution of the mammal species cited in the area since 1900. Of the 16 species historically cited, 9 have been detected in the present work, which represents 56.2%. The total absence of data on 5 of the potentially most abundant species such as Gerbillus amoenus (de Winton, 1902), Gerbillus gerbillus Olivier, 1801, Gerbillus tarabuli (Thomas, 1902), Pachyuromis duprasi Lataste, 1880 and Psammomys obesus Cretzschmar, 1828 is remarkable. Some data point to the drastic reduction of water resources experienced in recent years, as one of the causes of the apparent reduction of their populations. At the same time, other species with lower water requirement , such as Meriones libycus Lichtentstein, 1823 or Jaculus jaculus Linnaeus, 1758, have an apparent good state of conservation. The presence of Poecilictis libyca Hemprich & Ehrenberg, 1833 is confirmed after 32 years without being cited.El progresivo aumento del turismo de aventura en el entorno de las dunas de Erg Chebbi, amenaza, desde hace casi dos décadas, la conservación del único complejo dunar (Erg) de todo Marruecos. Con el propósito de valorar algunos de los efectos de esta actividad sobre la comunidad de mamíferos locales, entre marzo y abril de 2018 se llevó a cabo un muestreo intensivo utilizando 5 métodos de detección distintos. El objeto principal era evaluar la presencia y distribución actual de las especies de mamíferos presentes, teniendo como referencia las citadas en la zona desde 1900 (Aulagnier et al., 2017). De las 16 especies históricamente citadas, 9 han sido detectadas en el presente trabajo, lo que representa un 56.2%. Resulta de interés la ausencia total de datos sobre 5 de las especies potencialmente más abundantes como son: Gerbillus amoenus (de Winton, 1902), Gerbillus gerbillus Olivier, 1801, Gerbillus tarabuli (Thomas, 1902), Pachyuromis duprasi Lataste, 1880 y Psammomys obesus Cretzschmar, 1828. Algunos datos apuntan a la drástica reducción de los recursos hídricos experimentada en los últimos años, como una de las causas de la aparente reducción de sus poblaciones. Al mismo tiempo, otras especies de requerimiento hídricos menores, tales como: Meriones libycus Lichtenstein, 1823 o Jaculus jaculus Linnaeus, 1758, presentan un aparente buen estado de conservación. Se confirma la presencia de Poecilictis libyca Hemprich & Ehrenberg, 1833, tras 32 años de ausencia de datos

    Desarrollo de productos avanzados para la misión SEOSAT/Ingenio

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    Revista oficial de la Asociación Española de Teledetección[EN] SEOSAT/Ingenio is the future Spanish Earth Observation high spatial resolution mission in the optical domain. While Level 1 products, at-sensor geo-referenced radiances, are in an advanced phase of development under the framework of an industrial contractor, Level 2 products must be developed by the users. This fact limits the use of the satellite images only to the scientific community, restricting their use in other applications. The need to alleviate this limitation motivated this work, developed under the framework of a coordinate project, which aimed at offering a list of Level2 products to the Ingenio/SEOSAT user community. In this paper, we present the different methodologies developed to produce the proposed Level2 products, from surface reflectance at nominal sensor spatial resolution to images with higher spatial resolution or the possibility to create spatial and temporal mosaics. On the one side, for the surface reflectance product, we proposed an atmospheric correction algorithm based on using the spatial information, linked to a cloud screening algorithm and including morphological and topographic shadow corrections. On the other side, to enhance the image spatial resolution, we applied different fusion techniques using the multispectral and the panchromatic band, as well as some of the so-called “super-resolution” techniques. Finally, we provided different tools to develop spatial mosaics and temporal composites, directed to users interested on the exploitation of the Ingenio/ SEOSAT images.[ES] SEOSAT/Ingenio es la futura misión española de observación de la Tierra en el óptico en alta resolución es-pacial. Mientras que los productos de imagen a Nivel 1, radiancias geo-referenciadas a nivel de sensor, se encuentran en una fase avanzada de desarrollo existiendo para ello un contrato industrial, los productos de Nivel 2 deben ser de-sarrollados por los propios usuarios. Este hecho limita el uso de las imágenes a la comunidad científica, restringiendo sus posibles aplicaciones fuera de ésta. Así pues, bajo el marco de un proyecto coordinado y motivados por ofrecer productos de Ingenio/SEOSAT de Nivel 2 a disposición de cualquier usuario, se origina y desarrolla este trabajo. En este artículo se presentan los diferentes procesos desarrollados para la elaboración de productos a Nivel 2, desde reflectividades en superficie a la resolución nominal del sensor hasta imágenes con información espacial realzada y la posibilidad de crear mosaicos espaciales y compuestos temporales. Por una parte, en el caso de los productos de reflectividad en superficie se propone una técnica de corrección atmosférica basada en el uso de la información es-pacial, previo enmascaramiento de las nubes y una exhaustiva corrección de sombras morfológicas y/o topográficas. Por otra parte, para el realce de la información espacial, han sido evaluados diferentes métodos basados en la fusión de bandas multiespectrales con una banda pancromática así como la aplicación de técnicas llamadas de “Super-re-solución”. Finalmente, se proporcionan las herramientas necesarias para la realización de mosaicos tanto espaciales como temporales para todo tipo de usuarios interesados en la explotación de las imágenesEste artículo ha sido posible gracias al proyecto coordinado “Generación de Productos de Nivel 2 para la Misión INGENIO/SEOSAT”, ESP2013- 48458-C4-1-P, subvencionado por el Ministerio de Economia y Competitividad dentro del Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia.Sabater, N.; Ruiz-Verdú, A.; Delegido, J.; Fernández-Beltrán, R.; Latorre-Carmona, P.; Pla, F.; González-Audícana, M.... (2016). Development of advanced products for the SEOSAT/Ingenio mission. Revista de Teledetección. (47):23-40. https://doi.org/10.4995/raet.2016.6569SWORD234047Blesius, L., & Weirich, F. (2005). The use of the Minnaert correction for land‐cover classification in mountainous terrain. International Journal of Remote Sensing, 26(17), 3831-3851. doi:10.1080/01431160500104194de Lussy, F., Kubik, P., Greslou, D., Pascal, V., Gigord, P., Cantou, J. P. 2005. Pleiades-HR image system products and quality. Proceedings of ISPRS Hannover Workshop 2005: High-Resolution Earth Imaging for Geospatial Information.Do, M. N., & Vetterli, M. (2005). The contourlet transform: an efficient directional multiresolution image representation. IEEE Transactions on Image Processing, 14(12), 2091-2106. doi:10.1109/tip.2005.859376Weisheng Dong, Lei Zhang, Guangming Shi, & Xiaolin Wu. (2011). Image Deblurring and Super-Resolution by Adaptive Sparse Domain Selection and Adaptive Regularization. IEEE Transactions on Image Processing, 20(7), 1838-1857. doi:10.1109/tip.2011.2108306Freedman, G., & Fattal, R. (2011). Image and video upscaling from local self-examples. ACM Transactions on Graphics, 30(2), 1-11. doi:10.1145/1944846.1944852Grodecki, J., & Dial, G. (2003). Block Adjustment of High-Resolution Satellite Images Described by Rational Polynomials. Photogrammetric Engineering & Remote Sensing, 69(1), 59-68. doi:10.14358/pers.69.1.59Liu, J. G. (2000). Smoothing Filter-based Intensity Modulation: A spectral preserve image fusion technique for improving spatial details. International Journal of Remote Sensing, 21(18), 3461-3472. doi:10.1080/014311600750037499Marini, A., Reina Barragan, F.J., Crippa, G., Harnisch, B., Fuente, I., Lopez, M., Cabeza, I., Zorita, D. 2014. SEOSAT/INGENIO – A Spanish High-spatial-resolution optical mission. International Conference on Space Optics. Tenerife, Spain, 7-10 octubre.Mekler, Y., & Kaufman, Y. J. (1982). Contrast reduction by the atmosphere and retrieval of nonuniform surface reflectance. Applied Optics, 21(2), 310. doi:10.1364/ao.21.000310Otazu, X., Gonzalez-Audicana, M., Fors, O., & Nunez, J. (2005). Introduction of sensor spectral response into image fusion methods. Application to wavelet-based methods. IEEE Transactions on Geoscience and Remote Sensing, 43(10), 2376-2385. doi:10.1109/tgrs.2005.856106Pons, X., Pesquer, L., Cristóbal, J., & González-Guerrero, O. (2014). Automatic and improved radiometric correction of Landsat imagery using reference values from MODIS surface reflectance images. International Journal of Applied Earth Observation and Geoinformation, 33, 243-254. doi:10.1016/j.jag.2014.06.002Sun, J., Xu, Z., Shum, H. Y. 2008. Image super-resolution using gradient profile prior. IEEE Conference on Computer Vision and Pattern Recognition (CVPR), 1-8.VICENTESERRANO, S., PEREZCABELLO, F., & LASANTA, T. (2008). Assessment of radiometric correction techniques in analyzing vegetation variability and change using time series of Landsat images. Remote Sensing of Environment, 112(10), 3916-3934. doi:10.1016/j.rse.2008.06.011Villa, G., Montoro, M.A. 1993. Ajuste radiométrico conjunto de varias imágenes de satélite para la realización de mosaicos de ortoimágenes. En Actas de la V Reunión Científica de la Asociación Espa-ola de Teledetección. Las Palmas de Gran Canaria, Espa-a, 10 a 12 de Noviembre, pp. 385- 394.Vivone, G., Alparone, L., Chanussot, J., Dalla Mura, M., Garzelli, A., Licciardi, G. A., … Wald, L. (2015). A Critical Comparison Among Pansharpening Algorithms. IEEE Transactions on Geoscience and Remote Sensing, 53(5), 2565-2586. doi:10.1109/tgrs.2014.2361734Wald, L., Ranchin, T., Mangolini, M. 1997. Fusion of satellite images of different spatial resolutions: Assessing the quality of resulting images. Photogrammetric Engineering & Remote Sensing, 63(6), 691-699.Zhang, Y., 2004. Understanding Image Fusion. Photogrammetric Engineering & Remote Sensing, 70(6), 657-661.Zhou, J., Civco, D. L., & Silander, J. A. (1998). A wavelet transform method to merge Landsat TM and SPOT panchromatic data. International Journal of Remote Sensing, 19(4), 743-757. doi:10.1080/01431169821597

    CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

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    Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

    Differential clinical characteristics and prognosis of intraventricular conduction defects in patients with chronic heart failure

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    Intraventricular conduction defects (IVCDs) can impair prognosis of heart failure (HF), but their specific impact is not well established. This study aimed to analyse the clinical profile and outcomes of HF patients with LBBB, right bundle branch block (RBBB), left anterior fascicular block (LAFB), and no IVCDs. Clinical variables and outcomes after a median follow-up of 21 months were analysed in 1762 patients with chronic HF and LBBB (n = 532), RBBB (n = 134), LAFB (n = 154), and no IVCDs (n = 942). LBBB was associated with more marked LV dilation, depressed LVEF, and mitral valve regurgitation. Patients with RBBB presented overt signs of congestive HF and depressed right ventricular motion. The LAFB group presented intermediate clinical characteristics, and patients with no IVCDs were more often women with less enlarged left ventricles and less depressed LVEF. Death occurred in 332 patients (interannual mortality = 10.8%): cardiovascular in 257, extravascular in 61, and of unknown origin in 14 patients. Cardiac death occurred in 230 (pump failure in 171 and sudden death in 59). An adjusted Cox model showed higher risk of cardiac death and pump failure death in the LBBB and RBBB than in the LAFB and the no IVCD groups. LBBB and RBBB are associated with different clinical profiles and both are independent predictors of increased risk of cardiac death in patients with HF. A more favourable prognosis was observed in patients with LAFB and in those free of IVCDs. Further research in HF patients with RBBB is warranted

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access
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